<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <link rel="stylesheet" href="./grid-system.css">
  <style>
    .row {
      width: 500px;
      height: 10px;
      border: 1px solid red;
    }
    .row .span1 {
      height: 10px;
      border: 1px solid #ccc;
    }
  </style>
</head>
<body>

<div class="row">
  <div class="span1"></div>
  <div class="span1"></div>
  <div class="span1"></div>
  <div class="span1"></div>
  <div class="span1"></div>
</div>
</body>
</html>
